# set variable, check items in PKG symbol table
$ perl -Mstrict -e '$PKG::foo=1; print keys %PKG::'
foo

$ perl -Mstrict -e '$foo=1; print keys %main::'
Global symbol "$foo" requires explicit package name at -e line 1.
Execution of -e aborted due to compilation errors.

$ perl -Mstrict -e 'our $foo=1; print grep {/foo/} keys %main::'
foo
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I don't understand what you are saying, and your code doesn't contradicts anything I said.

>perl -Mstrict -le"{ package PKG; $foo=1; }"
Global symbol "$foo" requires explicit package name at -e line 1.
Execution of -e aborted due to compilation errors.

>perl -Mstrict -le"{ package PKG; no strict 'vars'; $foo=1; } print fo
+r grep /foo/, keys %main::"

>perl -Mstrict -le"{ package PKG; our $foo=1; } print for grep /foo/, 
+keys %main::"

>perl -Mstrict -le"{ package PKG; no strict 'vars'; $foo=1; } print fo
+r grep /foo/, keys %PKG::"
foo

>perl -Mstrict -le"{ package PKG; our $foo=1; } print for grep /foo/, 
+keys %PKG::"
foo
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The strict pragma only protects the current namespace

No, remove the use strict; and the below will run without complaint.

package X;
use strict;
sub one { 1 }

package Y;
$yy = 1;

package main;
exit;

__DATA__
Global symbol "$yy" requires explicit package name at x line 6.
Execution of x aborted due to compilation errors.
[download]

Be well,
rir

Update: added initial quote for clarity

It's kinda like no strict 'vars';, but it only applies to a single variable.

It means "yes, a package variable with that name exists, so don't complain about it."

And there are important differences to no strict 'vars', because the chosen namespace can be very different from what you expect: With our it's the stash of the package at declaration position, like with my where it's the lexpad at declaration position.

But with no strict 'vars' a "non-explicit" variable belongs to the actual package at the encounter position!

Thats a common but incomplete interpretation.

Correct, but only if you allow for poorly scoped variables. As I see things, my explanation is complete except in buggy programs. Put curlies around your packages when you have more than one in your file.

don't know what you mean, the following code is with curlies but produces different output for the two options.

use strict;

no strict "vars";  # option1
#our $x;        # option2

$x="main";

{
    package other;
    $x="other";
    print $x;
}

print $x;

__END__
1: othermain
2: otherother
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Cheers Rolf